Tears to the anterior cruciate ligament (ACL) are painful and often debilitating. Surgery for ACL injuries typically involves reconstructing the ACL using a graft material to replace the torn ACL. For example, ACL reconstruction surgery typically uses a graft to replace or support the torn ligament. The most common grafts are autografts from the patient (e.g., from a tendon of the kneecap or one of the hamstring tendons), though donor allograft tissue may also be used, as well as synthetic graft material. Although ACL reconstruction surgery is often referred to as ACL “repair” surgery, the current standard of care for ACL tears is to replace the torn ligament with a graft, rather than attempting to sew the torn ACL together. Merely sewing together the torn ACL has proven ineffective.
In general, ACL surgery may be performed by making small incisions in the knee and inserting instruments for surgery through these incisions (arthroscopic surgery) or by cutting a large incision in the knee (open surgery). During arthroscopic ACL reconstruction, the surgeon may make several small incisions around the knee. Sterile saline solution is pumped into the knee through one incision to expand it and to wash blood from the area. This allows the doctor to see the knee structures more clearly. The surgeon then inserts an arthroscope into one of the other incisions with a camera at the end of the arthroscope that transmits images of the internal region. Surgical drills may be inserted through other small incisions to drill small holes into the upper and lower leg bones where these bones come close together at the knee joint. The holes form tunnels through which the graft will be anchored. The surgeon may take an autograft at this point. The graft may also be taken from a deceased donor (allograft). In most prior art procedures, a graft may then be pulled through the two tunnels that were drilled in the upper and lower leg bones. The surgeon may secure the graft with screws or staples and close the incisions with stitches or tape.
Unfortunately, replacing the ACL with a graft material, which requires anchoring both ends of the graft material to bone, has proven technically difficult, resulting in a long surgical time, and may ultimately require a long recovery time. Replacement of native ACL material with graft material typically leads to the loss of native ACL proprioceptive fibers, and results in an alteration of the native ACL tibial footprint geometry. In some cases, removing autograft material from the patient may result in donor site morbidity, while donor allograft material presents an increased risk of HIV and Hepatitis C transmission.
In addition, anchoring tissue to bone, both in ACL procedure and more generally, has proven challenging. For example, anchoring tissue to bone in regions of limited access, such as the joints (e.g., knee, shoulder, hip, etc.) without having to displace, and potentially further damage, the joints has proven difficult. Access to the bone attachment site may be difficult in the confined region of the joint, making it particularly difficult to manipulate and secure an anchor within this region. One possible solution has been drill one or more passages through the bone from outside of the joint to form an opening in the joint space, and then anchor the tissue from the outside of the confined joint region, for example, by pulling the tissue, graft and/or suture through the bone passage to the opposite side of the bone. Unfortunately, this procedure results in poor fixation, as the tissue, graft and/or suture may stretch over time.
Thus, it would be desirable to provide devices, systems and methods for repair of the ACL that do not require the replacement of the ACL and the formation of multiple anchoring sites. The apparatuses (systems and devices) and methods for repair of the ACL described herein may address these concerns.